Clamp.



J. W. FRASER.

GLAMP.

APPLIOATNH FILED DEG.10,1909,

Patented Ja11.3, 1911.

JAMES WM. FRASER, OF CHARLOTTE, NORTH CAROLINA.

CLAMP.

Specification of Letters Patent.

Patented Jan. 3, 1911.

Application filed December 10, 1909. Serial No. 532,497.

To all whom it may concern:

Be it known that I, JAMES \VM. FRASER, a subject of Great Britain, and aresident of Charlotte, North Carolina, have invented certain new anduseful Improvements in Clamps, of which the following is aspecification, accompanied by drawings.

This invention relates to improvements in clamps, but more particularlyto suspension clamps for electric conductors, although the device may beused in any other connection in which it is found applicable.

The objects of the invention are to improve upon the construction ofsuch devices, facilitate the quick stringin and adjustment of a linewire, avoid siarp bends or kinks in the wire adjacent the clamp andafford simple and eflicient means for producing a wedging action tofirmly clamp the conductor or wire in the device.

In using the clamps with suspension insulators, the device is sodesigned that the conductor and strain insulator may be pulled intoapproximately the same line without producing undue bending strain onthe conductor.

The invention consists of the device sub- I stantially as hereinafterfully described and claimed in its preferred form in this specificationand shown in the accompanying drawings, in which Figure 1 is a side viewof a clamp embodying the invention; Fig. 2 is a sectlonal view on theline 22 of Fig. 1 looking in the direction of the arrows; Fig. 3 is aside view of the clamp connected to suitable suspension insulator; Fig.4 is a side elevation of a transmission line tower and suspensioninsulators; Fig. '5 is a side view of a clamp having a conductorinserted therein and protected by a shield; and Fig. 6 is an endelevation partly broken away of the top portion of the tower, with thesuspension insulator at an angle to the vertical.

Referring to the drawings, in which the preferred form of the inventionis illustrated, A represents a holder or'shoe forming the body portionof the clamp. This shoe is' preferably of hook-shaped or U- shaped formfor retaining the conductor B. The holder or shoe comprises the backportion 0, the retainin lip D forming a hook, the neck portion Fextending outwardly from the back C atan angle on the side toward thelip D, and connected to themed;

E is an eye F or other means for suspending the clamp.

The inner plain portion G of the neck E forms a bearing surface for thebeveled end H of a block or wedge J which block is adapted to enterbetween the back portion C and lip D of the clamp and bear upon theconductor 13, the bearing surface of said wedge J being preferablylongitudinally concave as shown. Suitable bolts K pass transverselythrough the block J and back portion 0 for tightening the parts andforcing the block inwardly to clamp the conductor. As the bolts aretightened, the beveled portion II of the block cooperates with thehearing portion G of the neck E and the block is forced downwardly.Preferably the beveled portion H of the block J is curved, so that thepoint of contact is tangent to the plain surface G of the neck E.

The base portion L of the body member A is sufficiently long to suitablysupport the conductor and is preferably convex in a longitudinaldirection on its inner surface and beveled at the ends 0 to avoid sharpcorners and prevent bends and undue strain in the conductor. The cornersP of the block or wedge J are also preferably rounded.

The device is shown in the drawings by way of illustration in connectionwith transmission line tower Q provided with the cross arms R andsuspension insulators S of any suitable character. In this instanceskirted insulators are shown hung one from another by the hooks T andeyes U. The clamp is adapted to be hung from the lowermost insulator Sas shown in the drawings. If desired, a shield or sleeve V may inclosethe conductor B within theclamp to protect the wire from abrasion or toprotect the wire from arcs. The clamp is so designed that if the boltsare not properly tightened or if under any abnormal stress-the conductorshould pull through the clamp, very little or no abrasion will occur.

In using the clamps in connection with suspension insulators, the mainbody portion .A of a clamp is attached to the lower end of a suspensioninsulator and the conductor after being pulled up to the roper sag isplaced in the groove of the b0 y portion A. After final adjustment as totension and sag of the wire, the body member of the clam and theinsulators are adjusted in a vertica line, and then the block or wedge Jis placed in position and the parts tightened by the bolts so that astrong wedging and compressive action results, thus firmly fixing theconductor in theclamp. The action of the clamp is such that by adjustingthe bolts to the proper tension the conductor will break rather thanpull out.

In Fig. 6 a detail view is shown illustrating relative positions of thesuspension insulators, clamp and conductor, in which the conductor B hasassumed a position approximately in the same line with the insulators.

This may be due to various causes, as for ina groove provided with abottom portion inwardly convex in a longitudinal direction for thereception of a conductor or other art to be clamped, the outer ends ofthe bottom of the groove being cut away, a wedge or block having abottom portion concave in a longitudinal direction and adapted to entersaid groove, a bearing portion on the holder, a beveled portion on thewedge cooperating with said bearing portion and means for tightening theparts to force the block or wedge into the groove.

2. A suspension clamp for electric conductors, comprising a holder orshoe having a groove in its base portion, the outer ends of the bottomof the groove being beveled, a neck extending outwardly at an angle tosaid holder and provided with a bearing surface, a wedge adapted toenter said -groove and having a beveled outer end adapted to cooperatewith the bearing surface of said neck, and transverse bolts assingthrough the wedge and holder for tightenmg the parts.

3. A suspension clam for electric conductors, comprising a ho der orshoe having a back portion, a retaining lip forming a hook, a neckportion extending outwardly at an angle from the back on the side towardthe lip, a block or wedge having a beveled end adapted to bear againstthe neck portion, and bolts passing transversely through the block andback portion of the shoe for tightening the parts and forcing the blockinwardly to clamp the conductor.

4. A suspension clamp for electric conductors, comprising a holderprovided with a groove for the reception of the conductor, a neckportion on said holder extending at an angle thereto, a bearing surfaceon said neck, a block adapted to enter the groove in the holder, meansconnecting said block and holder and means on said block for cooperatingwith said bcaring surface to force 5 the block into the groove.

In testimony whereof I have signed this specification in the presence oftwo subscrib- 111g witnesses.

JAMES \VM. FRASER.

Witnesses:

E. O. MARSHALL, L. C. MoRmsoN.

